A series of special supercomputers made by IBM that had the express purpose of beating the chess grandmaster Garry Kasparov. The initial hardware was designed as a hobby by university student Feng-hsiung Hsu, who was hired by IBM upon graduation to complete the task.

The first version of Deep Blue lost against Kasparov in 1996 by a score of 2 - 4. It was improved and in a 1997 rematch it won 3.5 - 2.5, after which it was dismantled and the project discontinued. The match caused a certain amount of controversy when Kasparov suggested the computer may have been receiving human help during play.

The hardware that beat Kasparov was capable of thinking to a depth of 40 ply and operated at 11.38 gigaflops.